Filter



FIG. 1 is a front, top, and right side perspective view of a filter;

FIG. 2 is a rear, bottom, and left side perspective view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a left side elevational view thereof;

FIG. 8 is a right side elevational view thereof; and,

FIG. 9 is a view of a section taken at line 9-9 in FIG. 3.

The broken lines shown in the figures are for the purpose of illustrating portions of the filter that form no part of the claimed design. 

CLAIM The ornamental design for a filter, as shown and described. 